In order to obtain a high-yield

high-efficiency and high-quality cultivation technique

this study was carried out to research the effects of film mulching period and nitrogen application rate on the soil water consumption characteristics

grain yield and quality of spring maize in dry lands of eastern Gansu province of China. The field experiment used a split-plot design. The main plot treatment was film mulching period. There were two levels of film mulching in autumn (mulching in farm slack season) and in spring (film mulching before seeding). The subplot treatment was nitrogen application rates

which include seven levels of nitrogen

0 kg/hm2 (CK)

75 kg/hm2 (N75)

150 kg/hm2 (N150)

225 kg/hm2 (N225)

300 kg/hm2 (N300)

375 kg/hm2 (N375)

and 450 kg/hm2 (N450). The 0-300 cm soil moisture content of autumn time and spring maize season

yield traits

dry matter accumulation and grain quality were measured. The results showed that:(1) Compared with film mulching in spring

film mulching in autumn significantly increases the soil water storage by 54.0~97.7 mm at 0-200 cm depth

and by 53.9~108.8 mm in 0-300 cm depth. (2) Long-term nitrogen application significantly reduced soil water storage at 0-300 cm during each growth period compared with CK. (3) Compared with the no film mulching

film mulching in autumn significantly reduced soil water consumption by 47.2~55.7 mm. (4) The water consumption was higher at middle maize growth stage than at early stage and late stage. The total water consumption of maize in the whole growth stage was 38.6~86.7 mm higher in autumn mulching than in spring mulching. This was closely related to soil water content before seeding. (5) The highest grain yield and water use efficiency was in treatment N225 kg/hm2. The average grain yield of different N application treatments in autumn mulching was 5.2% higher than that of spring mulching. The pure N225 kg/hm2 treatment also had the highest dry matter accumulation in different growth stages and harvest index. In addition

nitrogen application significantly affected crude protein

crude fat

and ash content. Therefore

the combination of film mulching in autumn and N 225 kg/hm2 could significantly increase the yield and water use efficiency of spring maize

optimize the yield composition

and improve grain quality. It is a suitable planting mode for efficient and high-quality maize production in the drylands of the eastern Gansu Province.